<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
    <style>
        div{
            width: 400px;
            height: 400px;
            background-color: red;
        }
    </style>
</head>
<body>
    <div></div>
    <script>
        var oDiv = document.getElementsByTagName('div')[0];

        oDiv.addEventListener('mousemove', throttle(center, 1000));

        function center(e){
            console.log('核心代码');
            console.log(this);
            console.log(e);
        }

        function throttle(fn, time){
            var lastTime = 0;
            return function(e){
                var nowTime = Date.now();
                if (nowTime - lastTime < time){
                    return;
                }
                lastTime = nowTime;
                fn.call(this, e);
            }
        }
    </script>
</body>
</html>